1. Field of the Invention
The invention relates to a load measuring apparatus.
2. Description of the Prior Art
Conventional load measuring systems operate on the principle of, for instance, displacement sensor elements being attached by glueing onto a complex mechanical system, consisting of wire strain gauges and measuring their deformations optically or electrically, respectively. The high rigidity of this load measuring system results in high critical frequencies and therefore in advantages when measuring dynamic stresses. The attachment of these sensor elements, however, is a complicated process requiring a high degree of dexterity and precision, or the alignment of a measuring bridge thus established is difficult to obtain.
An additional method of record for the measuring of loads consists in hodometry by means of a conventional displacement sensor at a flexional spring, dimensioned in accordance with the area of application of the measuring device, and the load impact point being properly selected. In this instance, care must be taken that the resulting lift of the flexional spring is sufficiently high for the displacement sensor.
It is not possible to make this lift too small, so that a low frequency of the load measuring system as such is the result. An additional disadvantage consists in the fact that the number of the movable parts is increased by the necessary load travel, resulting in problems of attrition which reduce the dependability of the load measuring system.